1. Field of the Invention
The present invention relates to a magneto-optical recording medium on which rewriting is possible, and more particularly to a magneto-optical recording medium comprising a substrate and a recording layer exhibiting perpendicular anisotropy formed thereon, the recording layer comprising (i) at least a transition-metal layer and a rare-earth-metal layer, or (ii) at least two transition metal--rare earth metal alloy layers, which are alternately overlaid on each other, and each of the layers further comprising a precious metal in an amount of 1 atom % to 10 atom %.
2. Discussion of Background
Recently, magneto-optical recording media on which information can be written in, read out, and rewritten by means of a laser beam have been actively studied, developed and are already being used in practice. A magnetic layer exhibiting perpendicular anisotropy comprising an amorphous alloy of a rare-earth-metal and a transition-metal is conventionally used as a recording layer for such a magneto-optical recording medium. In addition, a magnetic layer formed by overlaying two amorphous alloy magnetic layers alternately, or by overlaying a rare-earth-metal layer and a transition-metal layer alternately has been proposed in order to improve the coercive force Hc, the C/N ratio and other magneto-optical characteristics of the magneto-optical recording media, as disclosed in Japanese Laid-Open Patent Applications 59-217247, 61-108112, 62-26659, 62-71041, 61-128041, 62-137753.
However, while the coercive force Hc and the C/N ratio of such a recording layer can be improved, problems exist with a lack of long-term stability, so that the coercive force Hc and the C/N ratio deteriorate with the passage of time gradually.